<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<meta name="viewport" content="width=device-width, initial-scale=1">
		<title>my web site</title>
	</head>
	<body>
		<script>
			fn1();
			function fn1(){
				alert(1+1);
			}
			fn2();
			function fn2(){
				alert(2+2);
			}
			fn3();
			function fn3(){
				alert(4+4);
			}
			
			function fn(a,b){
				alert(a+b);
			}
			fn(1,1);
			fn(2,2);
			fn(4,4);
			
// 			fn3();
// 			function fn3(){
// 				alert(0);
// 			}
			
		</script>
	</body>
</html>